Rolling mill drive



L. W. FALK ROLLING MILL DRIVE Jan. 29, 1952 3 Sheets-Sheet 1 Filed April 12, 1945 INVENTOR Louis 146 Fczlk ATTORNEK Jan. 29, 1952 w L ROLLING MILL DRIVE 3 Sheets-Sheet 2 Filed Apri}. 12, 1945 l I u INYENTOR. L on 15 WZFaZk ATTORNEY Jan. 29, 1952 w. FALK 2,583,935 ROLLING MILL DRIVE Filed April 12, 1945 5 sheets-sheet 5 FIG. 3.

43 II VVENT LouzsW. R

AT TORNEYI Patented Jan. 29, 1952 ROLLING MILL DRIVE Louis W. Falk, Milwaukee, Wis., assignor to The Falk Corporation, Milwaukee, Wis, a corporation of Wisconsin Application AprillZ, 1945, Serial No. 587,953

1 This invention relates to rolling mill drives. In the rolling of strip steel, and particularly so-called temper rolled steel, it is common practice to pass the material between two pairs of rolls, sometimes arranged in a single stack, the

second pair being driven at a speed higher than that of the first pair so as to tension or stretch the material as it passes from the first to the second pair. The two pairs of rolls are commonly mechanically interconnected through in- 4 termeshing gears so as to insure the required positive and accurate control of the difference in roll speeds.

The roll speed differential is not large, usually about ten percent or less, but a fine adjustment thereof within that narrow range is highly desirable in order to obtain the particular degree 1 of stretch best suited for the work at hand.

One object of the present invention is to provide a rolling mill drive readily adjustable may manner to satisfy the above requirements.

Other more specific objects and advantages will appear, expressed or implied, from the following description of a rolling mill drive constructed in accordance with the present invention.

In the accompanying drawings: Figure l is a vertical longitudinal sectional view of a rolling mill drive embodying the present invention. 5

Fig. 2 is a fragmentary horizontal sectional view thereof taken substantially along the the 2-2 of Fig. 3.

Fig. 3 is an end elevational view with the change gears shown in the same position as in Fig. 2.

Fig. 4 is a diagrammatic view illustrating a different arrangement of change gears.

Fig. 5 is a view similar to Fig. 4 illustrating a i The rolling mill drive selected for illustration includes upper and lower parallel shafts It and H for connection in driving relation with separate upper and lower pairs of rolls, respectively, of a conventional mill of the type hereinabove mentioned.

The lower shaft H is journalled in and extends through an appropriate housing l2 and is I,

driven by suitable means such as an electric mo- I tor connectable to the rear end l3 thereof.

The upper shaft in is also journalled in the 5 Claims. (Cl. 74- 681) housing l2 and is connected in driving relation with shaft H through a suitable planetary gear set operable to effect operation of shaft ill at any of a plurality of selective speeds within a narrow speed range.

The planetary gear set shown comprises a cage i4 supported at opposite ends in appropriate bearings 15 and It for rotation about the axis of "shaft ID. In this instance the cage is composed of a central section I! and end heads is bolted or otherwise rigidly united thereto, as partially indicated particularly in Fig. 2. The cage l4 provides a revolving support for a pair of planet members, each journalledyat opposite ends in bearings l9 and 20 carried by the cage end heads l8, and each comprising a gear 2! integrally connected to a pinion 22 coaxially aligned therewith. Each planet gear 2| meshes with a sun pinion 23 carried by the shaft l0, and each planet pinion 22 meshes with a sun gear 24 coaxially aligned with pinion 23 and supported in bearings 25 and 25 in the cage M.

The sun gear 24 is connected in driving relation with the shaft II and for that purpose shaft ll is provided with a pinion 21 that meshes with a gear 28, the latter being preferably flexibly connected to sun gear 24 in order to avoid disturban'ces and wear that might otherwise result from slight misalignment between those gears. In this instance this is accomplished by mounting the gear 28 on a tubular shaft 29 journalled in bearings 39 and 3| in the housing, and by coupling the tubular shaft 29 to an elongated torsion shaft 32 that extends loosely therethroug'h from the gear 24. A dental coupling of a well known type, such as shown at 33, provides a satisfactory flexible driving connection between the shafts 29 and 32. Shaft 32 is aligned with shaft l0 and carries the sun gear 24.

The several pinions and gears hereinabove specifically mentioned are preferably proportioned so that as the speed of the cage l4 approaches zero, the shaft l0 rotates at a speed approaching the mid-point of its operating range. The arrangement is such that the speed of shaft ill will be reduced whenever the cage [4 is permitted to rotate in the direction of shaft Ill and increased whenever the cage rotates in an opposite direction. The speed of the shaft [0 may thus be varied and controlled by regulating the speed and direction of rotation of the cage. Although rotation of the cage may be regulated in various ways, a change-speed gear train is preferably employed for this purpose, this gear train serving to connect the cage with the shaft ll. so that the speed of the shaft It) may always be definitely related to that of shaft II.

I The change-speed gear train shown includes a pinion 34 meshing with a ring gear 35 carried by and rotating with the cage l4. The pinion 34 is carried by a shaft 36 journalled in the housing l2 and carrying a gear 31 that meshes with a pinion 38- on a shaft 39. The shaft 39 is journalled in the housing and projects through the rear end wall 44 thereof. A gear 4| on the projecting end of the shaft 39 meshes with a pinion 42 whose supporting shaft 43 is fashioned to detachably receive either of a pair of intermeshing change gears 44 or 45. In this instance the small gear 44 is shown on shaft 43 while the other larger gear 45 is shown detachably mounted on a shaft 46 which also carries a pinion 41 meshing with a gear 48 on the tubular shaft 29. The shaft 46 is thus permanently connected to the shaft H'through the gear train 4'1, 43, 28, and 21. i

. For a purpose which will hereinafter appear, the shaft 43 is preferably mounted for adjustment about the axis of shaft 39 with pinion 42 in mesh with gear 4| in all positions of adjustment of shaft 43. In this instance the shaft 43 is shown journalled in a barrel 49 carried by the end of plate-like crank 50 which is supported by ahollow hub 5! rotatably supported in the housing end wall 46, the shaft 39 being centered with respect to the supporting hub 5| by an appropriate bearing 52 within the hub.

In the change-speed gear train above described the several gears and pinions are preferably proportioned so that, with the small change gear 44 on. shaft 43 and the large change gear 45 on shaft 46, the cage I4 rotates in a direction opposite that of the shaft l6 and at a rate such as to cause the shaft ID to rotate at a speed closely approximating that of shaft I I. By interchanging the change gears, so that large gear 45 is on shaft 43 and small gear 44 is on shaft 46, thecage l4 may be caused to rotate atv a much lower speed to thereby effect a substantial reduction in the rate of rotation of the shaft [0. Additional intermediate speeds of the shaft I!) may be obtained by the use of additional change.

gears of other sizes. For instance, by replacing the small change gear 44 with a thirdchange gear 53 of a size intermediate that'of gears 44.

and 45, andby adjusting the shaft 43 and its supporting arm 53 into a position where the gear 53 will mesh with the large gear 45, as indicated in Fig. 4, oneintermediate speed of the shaft.

may be obtained; and by interchanging these gears 53 and 45, so that gear 53 is on shaft 46 and gear 45 is on shaft 43, a lower intermediate speed of shaft l6 may be had.

The rate of operation of the-shaft [0 may be further reduced by the use of an idler gear between the change gears. As indicated in Figs. and 6 for instance, an idler gear 54 is shown .detachably fixed to a stub shaft 55 journalled in a cage 56 mounted on and projecting rearwardly from the housing end wall 40. In this instance the idler gear 54 is shown meshing with the large change gear 45 on shaft 46, and the shaft 43 and its supporting arm 50 have been adjustedinto a position, such that the small change gear 44 meshes with the idler gear 54. With this arrangement of gears the cage I 4 ro- -tates at the same relatively high speed as when the change gears 44 and 45 are directly engaged,

.. but in an opposite direction (in the same direction as the shaft l0) thereby causing the shaft below the range of speeds obtainable with the various change gear combinations described in the immediately preceding paragraph.

Rotation of the shaft Ill at other speeds higher than the above mentioned minimum are obtainable by the use of a suitable idler gear with any of the several change gear combinations hereinabove described. As indicated in Fig. 7 for instance, an idler gear 54' may be substituted for the idler 54 on shaft 55, the idler 54 being of a size to mesh with the small change gear 44 on shaft 46, and the crank arm 56 being adjusted so that the large change gear 45 on shaft 43 meshes with idler 54'. With the gears thus arranged, the cage I4 is caused to operate at low speed in the same direction as that of shaft l0, causing the latter to rotate at a speed higher than the above mentioned minimum but below any speed obtainable without an idler.

From the foregoing it will be noted that a heavy duty drive for rolling mills and the like has been provided by which one roll of a mill -may be caused to operate at any of a plurality of selected speeds each bearing adefinite predechange in a change-gear combination easily accessible and conveniently. arranged for the purpose. It will be further noted that although the torque .load on each roll driving shaft is heavy, the torque reaction between the planetary cage and the change-speed gear train is only a fraction of the load on the associated roll driving shaft, and since the torque reaction between the change gears is relatively light, they may be and are of small size convenient for handling and therefore easily replaceable. I

In the planetary gear set shown provision is made for effecting an accurate positional relation between the teeth of bothplanets and those of the sun gears, so that the total torque transmitted from one sun gear to the other through the planets may be substantially equally divided In this instance the several sun and planet gears shown are of the single helical type in order to obtain smooth and quiet gear action characthis instance the gear 2! of one planet is splined on its supporting shaft, as indicated at 60, for

this purpose, and suitable means such as studs 6! coact with a collar 62 to axially position the gear 2| on its shaft.

The desired positionalrelation .between the planets andsun gears may be effected in. the following manner. With the cage I1 and one of the sun gears 24 fixed against rotation, the other sun gear 23 is rotated in one direction until its teeth are brought into firm contact with those of the gear 2| of the upper planet (Fig. 1.) and until the teeth of the other gear 22 of that planet are brought into firm contact with those of the fixed sun gear 24. Then, while the sun gear 23 is held in the position of last adjustment, the gear 2| of the lower planet is adjusted axially until its helical teeth make firm contact with those of sun gear 23 and react thereon to establish firm contact between the teeth of the connected gear 22 and those of other sun gear 24. The axial adjustment of the pinion 2| must be in a direction such that the resulting reaction thereof on the sun gear 23 urges the latter to rotate in a direction opposite to that of its initial rotation. Thereafter, while the sun gear 23 is still held against rotation, the studs 6! are anchored to the collar 62 to thereby securely fix the connected gear 2! in its position of last adjustment. It will be noted that the above method of adjustment establishes initial contacts between each sun gear and both planets with these contacts so related that no torque can be transmitted from either sun gear through its initial contact with one planet without producing a simultaneous torque reaction through its initial contact with the other planet.

Various changes may be made in the rolling mill drive hereinabove specifically described without departing from or sacrificing the advantages of the invention as defined in the appended claims.

I claim:

1. A rolling mill drive comprising a first shaft connectable in driving relation with a mill roll, a second shaft parallel thereto connectable in driving relation with another mill roll, a third shaft aligned with said first shaft, heavy duty gearing maintaining a definite speed relation between said second and third shafts, heavy duty planetary gearing connecting said first and third shafts, and control means reacting on said planetary gearing for regulating and determining the speed ratio between said mill rolls.

2. A rolling mill drive comprising a first shaft connectable in driving relation with a mill roll, a second shaft parallel thereto connectable in driving relation with another mill roll, a third shaft aligned with said first shaft, heavy duty gearing maintaining a definite speed relation between said second and third shafts, heavy duty planetary gearing connecting said first and third shafts, and adjustable means connected to said third shaft and reacting on said planetary gearing to regulate the speed ratio between said mill rolls.

3. A rolling mill drive comprising a first shaft connectable in driving relation with a mill roll, a. second shaft parallel thereto connectable in driving relation with another mill roll, a third ill shaft aligned with said first shaft, heavy duty gearing maintaining a definite speed relation between said second and third shafts, heavy duty planetary mechanism connecting said first and third shafts, said planetary mechanism including a relatively low speed rotor, and a gear train connected to said third shaft and reacting on said rotor to control the planetary action of said mechanism, said gear train including relatively high speed change gears effective to regulate and determine the speed of said rotor.

4. A rolling mill drive comprising a first shaft connectable in driving relation with a mill roll, a second shaft parallel thereto connectable in driving relation with another mill roll, a third shaft aligned with said first shaft, heavy duty gearing maintaining a definite speed relation between said second and third shafts, a pair of coaxial gears connected to said first and third shafts respectively, a rotor, a set of planet gears carried by said rotor and engaged with said pair of gears, and means effective to change the rate and direction of operation of said rotor to thereby regulate the speed ratio between said mill rolls.

5. A rolling mill drive comprising a first shaft connectable in driving relation with a mill roll, a second shaft parallel thereto connectable in driving relation with another mill roll, a pair of coaxial gears, one of said gears being connected to rotate with said first shaft, the other of said gears being connected in driving relation with said second shaft, a rotor, a set of planet members carried by said rotor, each of said planet members including a pair of coaxial gears of different diameters each engaged with one of first named pair of gears, and means for controlling said rotor to thereby control the speed ratio between said mill rolls.

LOUIS W. FALK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,149,816 Fay Aug. 10, 1915 1,217,427 Fast Feb. 27, 1917 1,441,707 Oslund Jan. 9, 1923 1,574,383 Fraser Feb. .23, 1926 1,590,902 Natisch June 29, 1926 1,669,411 Clark May 15, 1928 1,852,282 Biggert Apr. 15, 1932 1,962,581 Carroll a- June 12, 1934 1,967,559 Schreck July 24, 1934 2,014,138 Kuhn Sept. 10, 1935 2,144,307 Hallden Jan. 17, 1939 2,163,672 Ferris June 27, 1939 2,180,202 Hallden Nov. 14, 1939 2,212,241 Mayo Aug. 20, 1940 2,322,247 Mercier June 22, 1943 

